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Input circuit for connecting antennas.
Speaker and headphone connection details.
Operating the receiver for phone and broadcast.
Operating the receiver for CW signals.
Using the crystal filter for phone reception.
Function and calibration of the S-meter.
Procedures for alignment and service.
Explanation of superheterodyne theory and single signal operation.
Initial adjustments for Intermediate Frequency transformers.
Final adjustments for Intermediate Frequency transformers.
Procedure to verify crystal filter operation.
Matching, tracking, and uniform gain in circuits.
R.F. gain control and S-meter functionality.
Description of the HRO-SPC self-contained unit.
Details of the HRO Junior receiver variant.
Pricing for various HRO receiver models.
Pricing for HRO receiver accessories and cabinets.
Pricing for HRO receiver power supply units.
Description of the single signal receiver unit.
Details on the worm drive tuning system.
Ganged plug-in coils for band-spread tuning.
Overview of the nine-tube high-performance circuit.
Input circuit for connecting antennas.
Speaker and headphone connection details.
Operating the receiver for phone and broadcast.
Operating the receiver for CW signals.
Using the crystal filter for phone reception.
Function and calibration of the S-meter.
Procedures for alignment and service.
Explanation of superheterodyne theory and single signal operation.
Initial adjustments for Intermediate Frequency transformers.
Final adjustments for Intermediate Frequency transformers.
Procedure to verify crystal filter operation.
Matching, tracking, and uniform gain in circuits.
R.F. gain control and S-meter functionality.
Description of the HRO-SPC self-contained unit.
Details of the HRO Junior receiver variant.
Pricing for various HRO receiver models.
Pricing for HRO receiver accessories and cabinets.
Pricing for HRO receiver power supply units.
Description of the single signal receiver unit.
Details on the worm drive tuning system.
Ganged plug-in coils for band-spread tuning.
Overview of the nine-tube high-performance circuit.
General| Modes | AM, CW |
|---|---|
| IF | 456 kHz |
| Tuning | Variable frequency oscillator with bandspread |
| Type | Superheterodyne |
| Tube lineup | 6K7, 6J7, 6F6, 6H6 |
| IF Rejection | >60 dB |
| Sensitivity | 1 µV for 10 dB S+N/N |
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